[Solved] Identify the error in this Core Animation timing code: let animation = CABasicAnimation(keyPath: "opacity") animation.duration = 1.0 animation.timingFunction = CAMediaTimingFunction(name: .... | iOS Swift

iOS Swift - Animations

Identify the error in this Core Animation timing code:

let animation = CABasicAnimation(keyPath: "opacity")
animation.duration = 1.0
animation.timingFunction = CAMediaTimingFunction(name: .easeIn)
animation.fromValue = 1.0
animation.toValue = 0.0
view.layer.add(animation, forKey: "fade")

AThe animation is missing a fillMode to keep final state.

BThe timingFunction property expects a string, not CAMediaTimingFunction.

CThe keyPath "opacity" is invalid for CABasicAnimation.

DThe timing function name should be .easeInEaseOut, not .easeIn.

Step-by-Step Solution

Solution:

Step 1: Check timingFunction usage
Using CAMediaTimingFunction(name: .easeIn) is correct and supported.
Step 2: Identify missing fillMode
Without setting fillMode and isRemovedOnCompletion, the animation resets after finishing, so the view returns to original opacity.
Final Answer:
The animation is missing a fillMode to keep final state. -> Option A
Quick Check:
Missing fillMode causes animation to revert [OK]

Quick Trick: Add fillMode and isRemovedOnCompletion to keep final state [OK]

Common Mistakes:

Assuming .easeIn is invalid timing function name
Thinking timingFunction needs a string
Ignoring fillMode and completion behavior

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More iOS Swift Quizzes

Identify the error in this Core Animation timing code:

Step 1: Check timingFunction usage

Step 2: Identify missing fillMode

Final Answer:

Quick Check:

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